Microbiocidal Control in the Processing of Meat-Producing Four-Legged Animals

ABSTRACT

Methods of processing four-legged slaughter animals for consumption as meat and/or meat product(s) are described. The methods comprise I) contacting exterior surfaces of the live animal at least once with a microbiocidal solution formed from mixing together at least (i) water and (ii) at least one N,N′-bromochloro-5,5-dialkylhydantoin, such contacting occurring at least once when the animal is en route to being slaughtered but before it is killed by exsanguination; or II) contacting the carcass of the animal, after exsanguination, with a microbiocidal solution formed from mixing together at least (i) water and (ii) at least one N,N′-bromochloro-5,5-dialkylhydantoin or III) contacting at least one raw meat product and/or at least one processed meat product derived from the carcass. The contacting can be done one or more times in each of I), II), and III). Considerable advantages, which are described, are realized when using such methods.

REFERENCE TO RELATED APPLICATIONS

This application claims the benefit and priority of U.S. ProvisionalApplication No. 60/741,150, filed Dec. 1, 2005, the disclosure of whichis incorporated herein by reference.

BACKGROUND

Contamination of meat and meat products with various pathogens such asspecies of Listeria, Escherichia, Salmonella, Campylobacter, and others,is a problem that has existed for many years. While various othermicrobiocidal materials have been investigated for efficacy,antimicrobial substances typically used in actual practice in animalprocessing in slaughterhouses have been certain acids or certainchlorine-based biocidal agents such as sodium hypochlorite and calciumhypochlorite.

Huge numbers of four-legged animals are slaughtered and processed formeat and meat products consumed either by humans or pets. Such animalsinclude, for example, cattle, swine, horses, sheep, bison, rabbit,camel, kangaroo, alligator, crocodile, and other such existing orpotential sources of meat products, such as buffalo, goats, and llamas.These and other four-legged meat-producing animals used for food andfood products, e.g., deer, antelope, elk, squirrel, opossum, racoon, andnutria, are sometimes referred to collectively herein as four-leggedslaughter animals. Also the term “cattle” is used in a generic sense toinclude steers, heifers, cows, calves, and bulls; “swine” is used in ageneric sense to include hogs, sows, gilts, barrows, boars, and pigs;and the term “sheep” is used in a generic sense to include lambs, ramsand ewes.

Many four-legged slaughter animals, especially those from which beef orpork are obtained, are processed by high-output meat packing plantsusing state-of-the-art technology. Despite modem processing procedures,bacterial contamination of fresh meat occurs as an undesirable butunavoidable result of converting live four-legged slaughter animals intofood. Although current Good Manufacturing Procedures (GMPs) and/orrecent government regulations can reduce this contamination, the totalelimination of bacteria from fresh raw meats has not been achieved.Since deep muscle tissue is considered sterile in healthy animals,essentially all of the contamination originates from the carcasssurfaces. Soil, dust and manure on the hair, hides and hooves of theanimals represent one significant source of contamination. In addition,in some cases internal organs rupture during the removal process,resulting in further contamination of the carcass.

The general nature of the procedures and equipment used in theprocessing of four-legged slaughter animals for food is well-known tothose of ordinary skill in the art. Indeed, the literature in the fieldis extensive. For example, Outlines by G. R. Acuff, Ph.D., Professor ofFood Microbiology, Texas A & M University, of a pathogen reductiondialogue held May 6, 2002, describes a typical cattle slaughteroperation as involving the following steps: Cattle Receiving & Holding,Stunning, Exsanguination, Head and Shank Removal, Hide Removal,Evisceration, Carcass Splitting, Final Wash, and Chill. For hogslaughter, Dr. Acuff, id., identifies the following steps: Hog Receiving& Holding, Stunning, Exsanguination, Scalding, Dehairing, Singeing,Scraping & Polishing, Evisceration, and Wash & Chill. Other authors givedescriptions which are along the same general lines but which may varyto some extent. For example, slaughtering and processing of cattle asdescribed in a chapter entitled Overview of Meat Processing refers inpart to and explains the following processing steps: Pre-handling ofcattle, Stunning and bleeding, Dressing and hide removal, Evisceration,and Cutting and boning. In addition, the chapter further explains thatcarcass cutting and boning often take place after chilling but thatrecent developments have made it possible to undertake boning while thecarcass is still warm, a method referred to as “hot boning.” The samechapter describes and explains the steps in slaughtering and processingof pigs as including: Pre-handling of pigs, Stunning and bleeding,Dehairing and finishing, and Evisceration and splitting, with astatement in this latter section that, finally, the carcasses arechilled rapidly overnight before the subsequent processes of cutting andboning. Thus, anyone unfamiliar with the steps or operations involved inthe processing of four-legged slaughter animals for food can obtain avast amount of information by reference to the extensive literature onthe subject.

A number of the conventionally-used steps in the processing offour-legged slaughter animals for food constitute opportunities formicrobial and pathogen contamination. A need thus exists for one or morenew methods for reducing or eliminating such contamination of animalcarcasses or parts thereof during the processing of four-leggedslaughter animals for food. Another need is for the provision of one ormore methods which do not involve excessive expense in reducing oreliminating such contamination. A further need is for the provision ofone or more methods which do not involve undue interference withexisting slaughterhouse and/or meat packing operations.

Besides fulfilling the foregoing needs, it is vitally important that themethod used to fulfill the foregoing needs not cause any noticeabledegradation in the quality or properties of the meat from the carcasses,especially in the appearance and taste of the meat.

This invention is deemed to enable fulfillment of the foregoing needs,and to cause no noticeable degradation in the quality or properties ofthe meat from the carcasses resulting from the use or the methods ofthis invention.

BRIEF SUMMARY OF THE INVENTION

This invention provides methods for decreasing microbial contaminationof (I) a four-legged slaughter animal (for convenience hereinafter oftenreferred to simply as “animal”) being processed for slaughter and/or(II) the carcass of such animal and/or (III) raw meat products and/orprocessed meat products derived from the carcasses of such animals.

Pursuant to one embodiment of this invention, in the processing of afour-legged slaughter animal, the exterior surfaces of a livefour-legged slaughter animal are contacted prior to slaughter with anaqueous microbiocidal composition formed by mixing at least oneN,N′-bromochloro-5,5-dialkylhydantoin with an aqueous medium to form anaqueous microbiocidally-effective composition.

In another embodiment of this invention, at one or more suitable stagesduring the processing of the animal carcass, carcass surfaces of theslaughtered animal are contacted with an aqueous microbiocidalcomposition formed by mixing at least oneN,N′-bromochloro-5,5-dialkylhydantoin with an aqueous medium to form anaqueous microbiocidally-effective composition. Depending upon the typeof animal carcass being processed, such contacting can be conductedbefore, during and/or after removing the hide from the carcass, orbefore or after removing the hair and/or bristles from the carcass.

In still another embodiment of this invention, at one or more suitablestages before, during and/or after the preparation of raw meat productsand/or processed meat products such products are contacted with anaqueous microbiocidal composition formed by mixing at least oneN,N′-bromochloro-5,5-dialkylhydantoin with an aqueous medium to form anaqueous microbiocidally-effective composition. A few examples of rawmeat products include steaks, chops, rib sections, meat roast cuts,hams, loins, animal organs, trims, and ground meat. A few examples ofprocessed meat products include ready-to-eat deli products, sausages,frankfurters, and sliced meats.

Substantial benefits can be achieved by the use of an aqueousmicrobiocidally-effective composition formed from one or moreN,N′-bromochloro-5,5-dialkylhydantoins. Besides being more effective onan equal halogen basis than many chlorine-containing biocidal agentssuch as hypochlorite, the N,N′-bromochloro-5,5-dialkylhydantoins formaqueous microbiocidally-effective compositions that are less corrosiveto the nozzles, fittings, cabinets, transporting apparatus, and otherparts of the various washing, showering, spraying, and/or mistingsystems used. Moreover, because of their greater effectiveness asantimicrobials as compared to many chlorine-containing biocides,N,N′-bromochloro-5,5-dialkylhydantoins such asN,N′-bromochloro-5,5-dimethylhydantoin can be introduced into an aqueousmedium at suitably low dosage levels and yet form compositions havingenhanced microbiocidal effectiveness, and with no appreciable adverseeffect when applied to a live four-legged slaughter animal beingprocessed for slaughter. In addition, theN,N′-bromochloro-5,5-dialkylhydantoins form aqueous compositions thatare stable over a range of temperatures from as low as just above thefreezing point of the composition to about 70° C. and which throughoutthis temperature range are effective against microorganisms andpathogens even when such compositions are formed using low dosage levelsof the N,N′-bromochloro-5,5-dialkylhydantoin(s). Thus, themicrobiocidally effective compositions of this invention can beeffectively utilized under most, if not all, temperature conditionsencountered in the processing of four-legged slaughter animals, at leastfor meat. Furthermore, experimental results presented hereinafter haveshown that, surprisingly, the practice of this invention did not causenoticeable degradation in the appearance of meat treated with an aqueoussolution of BCDMH as compared to meat treated with aqueous bleachsolutions or aqueous solutions of lactic acid. Indeed, theseexperimental results indicate that the appearance of the meat tested wasessentially the same as the appearance of another portion of the samemeat cut treated with an aqueous solution of DBDMH or a suitably dilutedaqueous solution of Stabrom 909 concentrated aqueous biocide solution(Albemarle Corporation), a product formed in water from brominechloride.

Moreover, the greater water solubility of BCDMH (890 ppm at 75° F. (ca.24° C.) expressed as chlorine) as compared to DBDMH (405 ppm at 75° F.(ca. 24° C.) expressed as chlorine) provides BCDMH with some importantoperational advantages. In many high output meat packing plants, spaceto install the biocide feeder in an easily accessible location is notreadily available. The smaller area required for a BCDMH feeder systemrelative to a DBDMH system, is advantageous with respect to installationflexibility. For example, because of higher bromine output, a plantutilizing BCDMH may utilize a smaller number of biocide feeders than aplant utilizing DBDMH feeders. Also, because each point of applicationof aqueous biocide in the plant requires a certain bromine residual in acertain flow of water, the much higher output of bromine from a BCDMHfeeder to achieve the desired bromine residual, requires much less waterflow to the feeder for BCDMH than DBDMH. Since the source of water andthe feeder are often quite distant from each other, a need for providinga new line just for the feeder is disadvantageous and expensive. But,pursuant to this invention, oftentimes excess water supplied to existingequipment near the feeder can be employed thereby eliminating the needfor installation of a new special water line to the feeder. In otherwords, since BCDMH requires less than half the water flow of DBDMH, inmany situations this water source would have sufficient flow for BCDMHwhile that same flow would be insufficient for DBDMH. Thus a long run ofpipe that would be needed to supply the water demand to the feeder forDBDMH is avoided by use of BCDMH. Further, even if a long run of pipingneeds to be installed and a pump is needed to achieve the desired waterpressure, BCDMH would require smaller diameter pipe and a smaller, lessexpensive pump to achieve the desired residual. Thus, even though DBDMHis more effective as a biocide than BCDMH, the foregoing advantages ofBCDMH offset such effectiveness.

Various embodiments and features of this invention will be furtherapparent from the ensuing description, accompanying drawings, andappended claims.

International Application WO 2002/US/20236, published 9 Jan. 2003 as WO03/001931 A1, describes, inter alia, use of aqueous solutions of certainhalogen based microbiocides such as a solution formed in water frombromine, chlorine or bromine chloride, or any two or all three thereofand a water-soluble source of sulfamate anion; or at least one1,3-dihalo-5,5-dialkylhydantoin in which one of the halogen atoms is achlorine atom and the other is a chlorine or bromine atom and the alkylsindependently have 1-4 carbon atoms; or at least one1,3-dibromo-5,5-dimethylhydantoin in which one alkyl is methyl, and theother alkyl has 1-4 carbon atoms to disinfect carcasses and/or parts ofpoultry resulting from the processing of poultry. It is shown that thecolor of chicken skin and the taste of the chicken meat are notadversely affected by the disinfection processing used. Processedcarcasses of poultry have a coating of substantially water imperviousskin covering the meat. In contrast, carcasses of four-legged slaughteranimals after removal of the hide, have no such water imperviousprotective coating. As will be seen from test results hereinafter, ithas been shown that direct contact of an aqueousmicrobiocidally-effective composition of this invention with raw beefproduced virtually no perceivable change in the color of the meatindicating that the microbiocides used pursuant to this invention inappropriate proportions do not adversely affect the quality of the meat.Accordingly, the treatment of four-legged slaughter animals such ascattle with an aqueous microbiocidally-effective composition of thisinvention especially before hide removal, and/or carcasses of suchanimals after hide removal, should also have little, if any, effect uponthe quality of the meat.

It is also noteworthy that poultry processing especially in modem highlyautomated plants, involves at least in the chill tank, long periods oftime, e.g., an hour or so, during which the microbiocide can exert itsmicrobiocidal activity. In contrast, in high-output meat packing plantsand slaughterhouses in which cattle or pigs, or carcasses thereof areprocessed, hung for aging effects and/or cooling, sprays of relativelyshort duration are typically used. Therefore, the time available for amicrobiocide to exert its microbiocidal activity is usually considerablyshorter in such plants or slaughterhouses than in a plant processingpoultry for edible meat products.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram illustrating typical stages during theprocessing of cattle at which, pursuant to this invention, cattle and/orcattle carcasses can be contacted with the aqueousmicrobiocidally-effective compositions used pursuant to this invention.

FIG. 2 is a block diagram illustrating typical stages during theprocessing of swine at which, pursuant to this invention, swine and/orswine carcasses can be contacted with the aqueousmicrobiocidally-effective compositions used pursuant to this invention.

FURTHER DETAILED DESCRIPTION OF THE INVENTION

The aqueous microbiocidally-effective compositions of this invention areformed from components comprised at least of (i) water and (ii) at leastone N,N′-bromochloro-5,5-dialkylhydantoin. These components are mixed inmicrobiocidally-effective proportions, and such proportions can varydepending on various factors such as for example the animal speciesbeing processed, the time of the year the animals are being processed,the amount of microbial contamination on the animals being processed,the kind and extent of contamination to which the animals, carcasses,and/or parts thereof are exposed during the various operations conductedin a slaughter house or meat packing plant, and the type of object(s)being processed or prepared, whether live animal, animal carcass, rawmeat product, and/or processed meat product. In general, however, thecomponents water and at least one N,N′-bromochloro-5,5-dialkylhydantoinare proportioned such that an effective microbiocidal amount ofmicrobiocide formed from water and the one or moreN,N′-bromochloro-5,5-dialkylhydantoins is present in the resultantcomposition.

The amounts of one or more N,N′-bromochloro-5,5-dialkylhydantoins thatare dissolved in water to form an aqueous microbiocidally-effectivecomposition of this invention may be expressed in terms of bromineresidual. Thus in the practice of this invention the water is mixed withat least one N,N′-bromochloro-5,5-dialkylhydantoin microbiocidal agentin an amount to achieve a bromine residual of up to about 400 ppm(wt/wt) expressed as free bromine, preferably up to about 200 ppm(wt/wt) expressed as free bromine. More preferably, the amount of atleast one N,N′-bromochloro-5,5-dialkylhydantoin microbiocidal agentmixed with water achieves a bromine residual of up to about 100 ppm(wt/wt) expressed as free bromine, and still more preferably up to about50 ppm (wt/wt) expressed as free bromine. Typically a minimum bromineresidual of at least about 0.5 ppm (wt/wt) expressed as free brominefrom one or more N,N′-bromochloro-5,5-dialkylhydantoins will be usedespecially in those compositions that are used for sanitizing ordecontaminating raw meat products and/or processed meat products.Preferably a minimum bromine residual of at least about 10 ppm (wt/wt)expressed as free bromine, more preferably of at least about 20 ppm(wt/wt) expressed as free bromine, and still more preferably of at leastabout 50 ppm (wt/wt) expressed as free bromine from one or moreN,N′-bromochloro-5,5-dialkylhydantoins will be used especially in thosecompositions that are used for sanitizing or decontaminating livefour-legged slaughter animals and/or carcasses of such animals.Particularly preferred especially for sanitizing or decontaminating livefour-legged slaughter animals and/or carcasses of such animals areaqueous microbiocidally-effective compositions of this invention havinga bromine residual in the range of about 20 to about 100 ppm (wt/wt)expressed as free bromine from one or moreN,N′-bromochloro-5,5-dialkylhydantoins. Preferred compositions used forsanitizing or decontaminating raw meat products and/or processed meatproducts are compositions having a bromine residual in the range ofabout 0.5 to about 400 ppm (wt/wt) expressed as free bromine from one ormore N,N′-bromochloro-5,5-dialkylhydantoins. More preferred compositionsfor use in sanitizing or decontaminating raw meat products and/orprocessed meat products are compositions having a bromine residual inthe range of about 50 to about 200 ppm (wt/wt) expressed as free brominefrom one or more N,N′-bromochloro-5,5-dialkylhydantoins. Still morepreferred compositions for use in sanitizing or decontaminating raw meatproducts and/or processed meat products are compositions having abromine residual in the range of about 50 to about 100 ppm (wt/wt)expressed as free bromine from one or moreN,N′-bromochloro-5,5-dialkylhydantoins. The product solution istypically used at a temperature of about 1 to about 39° C., but can beused at higher temperatures, e.g., up to about 70° C., if desired. Theterm “expressed as free bromine” denotes the way the concentrations arecalculated and reported. It does not mean that free molecular bromine isnecessarily present. Instead, the solution contains bromine in whateverchemical form(s) it exists when theN,N′-bromochloro-5,5-dialkylhydantoin is dissolved in water.

Non-limiting examples of four-legged slaughter animals include cattle,swine, horses, sheep, bison, rabbit, camel, kangaroo, alligator,crocodile, and other such existing or potential sources of meatproducts, such as buffalo, goats, deer, antelope, elk, squirrel, rabbit,opossum, racoon, nutria and llamas. These and other four-leggedmeat-producing animals used for food and food products are sometimesreferred to collectively herein as four-legged slaughter animals. Also:the term “cattle” is used in a generic sense to include steers, heifers,cows, calves, and bulls; “swine” is used in a generic sense to includehogs, sows, gilts, barrows, boars, and pigs; and the term “sheep” isused in a generic sense to include lambs, rams and ewes.

There are two general types of four-legged slaughter animal processingwherein this invention is applicable. They are:

-   I) administration of aqueous microbiocidally-effective compositions    used pursuant to this invention to exterior surfaces of the live    four-legged slaughter animals being processed for slaughter; and-   II) administration of aqueous microbiocidally-effective compositions    used pursuant to this invention to the carcasses of    freshly-slaughtered four-legged slaughter animals being processed    for meat and/or meat products.    As noted above there is another category of processing wherein this    invention is applicable, which is:-   III) administration of aqueous microbiocidally-effective    compositions used pursuant to this invention to the raw meat    products and/or processed meat products derived from the slaughtered    animal at any suitable stage(s) before, during, and/or after any    operation used in the preparation and/or processing of such raw meat    products and/or processed meat products.    Type I Processing

As can be seen from the above, Type I processing pursuant to thisinvention relates to reducing microbiocidal contamination of meat and/ormeat products to be produced from the processing of the animals, bycontacting exterior surfaces of the animal during one or more of theinitial stages of the processing while the animal has not yet beenkilled. These stages include any pre-handling steps taken with theanimals before they are killed (i.e., while they are still alive) suchas receiving & holding the animal, moving the animal to the stunningarea, stunning the animal, and handling or moving the stunned animalbefore exsanguination. Thus, pursuant to an embodiment of thisinvention, exterior surfaces of the animal are contacted with one ormore aqueous microbiocidally-effective compositions of this inventionduring at least one such stage or step while the animal is still alive.

Preferably, prior to application of one or moremicrobiocidally-effective compositions of this invention to the liveanimal, areas such as animal hind quarters, legs and hooves and otherareas where fecal matter exists on the animals, are initially cleansedof fecal matter by hosing or use of sprays of at least water or aqueousdetergent solutions.

Whether or not such preferred cleansing is conducted, pursuant to thisinvention the live animal is exposed to spraying, showering, misting,partial bathing, or any other suitable method of applying at least oneaqueous microbiocidally-effective composition of this invention toexterior surfaces of the animal while it is still alive. Preferably suchat least one aqueous microbiocidally-effective composition of thisinvention is applied to substantially the entire animal before theanimal enters the area where exsanguination (i.e., bleeding and thuskilling) is to occur. This can be accomplished, for example, byproviding at least one shower zone and/or spray zone at a location wherethe animals are caused to move from holding areas toward theslaughterhouse or meat packing plant. As the animals pass through suchzone or zones, they are showered and/or sprayed with one or more aqueousmicrobiocidally-effective compositions of this invention so that theexterior of the animal becomes wetted by such composition. Such sprayscan be fixed or articulated sprays. Also, the shower and/or sprays canbe of different intensities so as ensure thorough wetting of the hideand flushing of filth from the animal. Preferably, the animal is thencaused to walk through a bath of aqueous microbiocidally-effectivecomposition of this invention so that at least the lower leg area andhooves of the animal are washed by such composition. Such bath caninclude subsurface forced spray jets to improve washing efficiency. Itis preferred to locate such bath outside of the slaughterhouse or meatpacking plant, and/or at least in a perimeter area of the slaughterhouseor meat packing plant, as such positioning will help ensure that theamount of microbiocidal contamination brought into the slaughterhouse ormeat packing plant is effectively minimized by practice of thisinvention. This in turn greatly reduces the likelihood of crosscontamination during subsequent processing operations conducted in theslaughterhouse or meat packing plant.

Another Type I operation pursuant to this invention is the applicationof mists of aqueous microbiocidally-effective composition of thisinvention to the animal in lieu of, or in addition to, sprays as theanimal moves toward the slaughterhouse or meat packing plant. Also thesequence of passage through zones can be varied, e.g., causing theanimal(s) to walk through a bath of aqueous microbiocidally-effectivecomposition can occur before or at the same time one or more showersand/or sprays are applied to the animal. Another option is to provide amisting zone in which at least one aqueous microbiocidally-effectivecomposition of this invention is applied to the animal after one or morezones where showering, spraying and/or bathing (in whatever sequence isdesired) of the animal with at least one aqueousmicrobiocidally-effective composition of this invention take(s) place.In short, any sequence of applying at least one aqueousmicrobiocidally-effective composition of this invention to the liveanimal can be used. Any such application preferably takes place as theanimal is moved toward the slaughterhouse or meat packing plant and/oris in a perimeter area of the slaughterhouse or meat packing plant.

Still another embodiment of the invention is a novel way of applying oneor more showers and/or sprays to the live animal. This is accomplishedby utilizing a portable shower and/or spray stall which may also containa misting and/or partial bathing zone. The animal or a procession ofanimals is caused to pass into and through such stall in which theexterior(s) of such animal(s) are contacted (e.g., showered, sprayed,etc.) with at least one aqueous microbiocidally-effective composition ofthis invention before proceeding into, or further into, theslaughterhouse or meat packing plant. Such portable shower or spraystall can be sized and adapted to be transported from one place toanother by means of an 18-wheeler truck-trailer or railroad car, or canitself be constructed as a unitary suitably-wheeled trailer adapted tobe transported from place to place by means of a truck tractor or farmtractor. Such trailer can be equipped with its own supply of aqueousmicrobiocidally-effective composition of this invention, or the trailercan draw from a supply of such composition located on the site whereusage is to occur. Similarly, the power to drive the pumps which feedthe aqueous microbiocidally-effective composition of this invention tothe shower(s), sprays, and/or misting devices can be generated by an onboard power supply or generator, or the power can be provided by thesite where usage is to occur. Preferably, the waste water from use ofsuch portable shower and/or spray stall is collected by the stallitself. After solids are removed from the recovered waste water and, ifnecessary, additional microbiocidally-effective composition of thisinvention is mixed with such solids-free waste water, the resultantwaste water can be reused in the portable shower and/or spray stall.This embodiment is especially useful in the case of small abattoirswhere, periodically, only one or a relatively small number of animalsare slaughtered, as a portable shower and/or spray stall can bedelivered from place to place for use at different small abattoirs whenthe animal slaughter operation is to take place therein.

Where more than one live animal bathing zone, showering zone, sprayzone, and/or misting zone is used pursuant to this invention, themicrobiocidally-effective concentrations of the respective aqueousmicrobiocidally-effective compositions of this invention used in suchzones can be the same or at least two such compositions can differ inconcentration. The actual concentration ranges are typically in theranges described above but can be increased to suit the needs of theoccasion, such as in cases where animals have been exposed toextraordinary amounts of fecal matter due to unusual circumstances suchas unanticipated microbiocidal contamination of a supply of animal feedor drinking water, sickness of some animals within a herd,transportation delays, or the like.

The temperature(s) of the aqueous microbiocidally-effectivecomposition(s) of this invention used in the above Type I processingpursuant to this invention can differ over a suitable range. Thus thecomposition(s) used can be applied after being heated to a suitable warmtemperature or conversely cooled to a suitable cooling temperature toassist in calming the animals as they approach the slaughterhouse ormeat packing plant, and thereby improve the movement of a procession ofanimals from the holding area to the slaughter house or meat packingplant and/or as they approach the stunning area. Also, by suitablyadjusting the temperature of the composition(s) it is possible toprevent or at least reduce heat-related sickness (e.g., heat stroke) ofstressed closely-packed animals.

Among additional advantages of the above Type I processing is that themicrobiocidal effectiveness of the aqueous microbiocidal compositionsformed by mixing one or more N,N′-bromochloro-5,5-dialkylhydantoins withan aqueous medium is suitably high even when using low dosage levels ofsuch compound(s). This in turn avoids or at least minimizes thelikelihood of adverse behavioral reaction of the animal if and when, forexample, the spray is applied to the eyes or otherwise comes intocontact with sensitive body parts of the animal. Avoidance orminimization of such adverse behavioral reaction of the animal isbeneficial in that the movement of a procession of animals to theslaughterhouse or meat packing plant and/or to the stunning area is notdisrupted.

In small abattoir operations where, periodically, only one or arelatively few animals are slaughtered, the above-described operationscan be conducted in various ways. For example, the animal(s) can besprayed by use of one or more hand held pressurized spraying deviceseach attached by a hose to a suitable supply of an aqueousmicrobiocidally-effective composition of this invention. Alternatively,the composition can be applied by use, for example, of mops, hand-heldrags, sponges, or scrubbing brushes, and/or simply by splashing the liveanimal with the composition of this invention from a pail or bucket. Inoperations such as these, care should be taken to ensure that effectivecoverage of the exterior animal surfaces by the applied aqueousmicrobiocidally-effective composition of this invention is achieved.Also, as in any operation where portions of the operator(s) may beexposed over and over again to a chemical solution, it is desirable forthe operator(s) to wear at least water-impermeable gloves and goggles,and preferably water-impermeable outer garments as well. As noted above,it is preferable to wash the animal with water before applying theaqueous microbiocidally-effective composition of this invention to theanimal.

Other places in the slaughterhouse or meat packing plant where anaqueous microbiocidally-effective composition of this invention can beapplied with desirable results to the animal while it is still alive arein the area where the animal is to be stunned and/or where the stunnedanimal is handled after stunning but before exsanguination is initiated.Such handling may include, for example, transporting and/or attachingthe stunned animal to a conveyor system. At such locations in theslaughterhouse or meat packing plant, application of an aqueousmicrobiocidally-effective composition of this invention to exteriorsurfaces of the stunned animal such as by means of a shower system,spray system, misting system or bath can be advantageous. Such anoperation can be used in addition to or in place of the application ofan aqueous microbiocidally-effective composition of this invention toexterior surfaces of the animal as it moves from the holding area towardthe slaughterhouse or meat packing plant and/or is in a perimeter areaof the slaughterhouse or meat packing plant, as described above. In allcases of Type I processing, it is preferred to ensure that the liveanimal has been thoroughly washed with water or aqueous detergentsolution at least once before applying the aqueousmicrobiocidally-effective composition of this invention to the animalbefore it is killed.

It is also possible pursuant to this invention to wash the live animalwith water or aqueous detergent solution and thereafter apply to theanimal while still alive, an aqueous mixture in which one or moresurfactants, detergents, wetting agents, hydrotropes, thickeners,foaming agents, defoaming agents, buffering agents, acids, bases,demulcents, humectants, emollients, vitamins, fatty acids, or similarfunctional additives are included in an aqueousmicrobiocidally-effective composition of this invention, provided thatthe one or more additives are not susceptible to oxidation byN,N′-bromochloro-5,5-dialkylhydantoin.

Type II Processing

As used anywhere herein including the claims, the term “carcass” denotesthe body of the slaughtered four-legged slaughter animal at any stage ofthe processing operations used to convert the dead animal into meat.Thus the term “carcass” includes (i) the whole slaughtered animal body,(ii) the trunk of the body remaining after removal of the head and/orlegs from the trunk of the animal, (iii) the severed head and thesevered legs themselves, and (iv) the parts of the trunk of the bodyafter it has been split in two (e.g., sagittally).

As used anywhere herein including the claims, the term “during” denotesa period of time either (i) throughout the entire time a given operationis being conducted or (ii) at some portion or portions of the time agiven operation is being conducted but not all of the time that suchgiven operation is conducted. For example the phrase “during hideremoval” means that some specified thing is done (i) at least throughoutthe entire time a hide removal operation is being carried out on a givencarcass, or alternatively, (ii) for one or more time periods—but notthroughout the entire time—a hide removal operation is being carried outon a given carcass. Note also that such hide removal operation (or otherspecified operation) need not be continuous in the sense, for example,that hide must be separated from the animal continuously from start tofinish of the operation on a given carcass. Such removal can becontinuous or non-continuous with pauses occurring during the overalloperation (e.g., hide removal), and thus the specified thing is doneeither (i) at least throughout the entire time a given operation (e.g.,hide removal) is being carried out on a given carcass including anypauses that occur in such operation, or alternatively, (ii) for one ormore time periods—but not throughout the entire time—a given operation(e.g., hide removal) is being carried out on a given carcass includingany pauses that occur in such operation.

As used anywhere herein, including the claims, the term “productsolution” denotes the aqueous solution that results from mixing togetherat least water and one or more N,N′-bromochloro-5,5-dialkylhydantoins.According to present theoretical concepts,N,N′-bromochloro-5,5-dialkylhydantoins, to at least some extent, losetheir original chemical structure when dissolved in an aqueous mediumand the resultant composition, whatever it may be, is denoted herein asa “product solution” as it is formed from such specified components.

As used anywhere herein including the claims, the term “directlyprecedes” means that the specified thing (e.g., contacting a carcasswith an aqueous microbiocidal composition) is done before the ensuingoperation (e.g., hide or skin removal) has begun without any interveningoperation being conducted except for transporting the carcass from theplace where the specified thing was conducted to the place where theensuing operation is to be done.

Pursuant to an embodiment of this invention, the external surfaces of anon-eviscerated carcass of at least one four-legged slaughter animal iscontacted at least once with an aqueous microbiocidally-effectivecomposition of this invention. This contacting can be effected byimmersing the carcass in an aqueous microbiocidally-effectivecomposition of this invention, by showering, spraying or misting thecarcass with an aqueous microbiocidally-effective composition of thisinvention, or by using any other method of applying the aqueousmicrobiocidally-effective composition of this invention so that it comesinto direct contact with the carcass before, during and/or after hideremoval or after hair and/or bristle removal, but in each case prior toevisceration. Thus in the case of animal processing where the hide isremoved followed by evisceration with or without an intermediate waterwash, the contacting in this embodiment of the invention should takeplace before, during and/or after the hide removal stage but before theevisceration operation commences. In the case of animal processing wherethe hide is not removed before evisceration (e.g., where the carcass issubjected to singeing or shearing to remove hair and/or bristles,followed by evisceration, with or without an intermediate water wash),the contacting in this embodiment of the invention usually should takeplace after the singeing or shearing but before the eviscerationoperation commences. It is also possible to cause the contacting tooccur during hair and/or bristle removal when the removal is conductedby a method other than singeing. In either such case (i.e., where hideis removed or where hide is not removed before evisceration), in amoving line of suspended spaced-apart carcasses, the contacting shouldbe conducted such that the exposed surfaces of each carcass arecontacted with and remain in contact with the aqueous microbiocidalsolution used pursuant to this invention for a period of at least 2seconds, and preferably for a period of at least 30 seconds. Also ineither such case the aqueous microbiocidally-effective composition ofthis invention can be preheated so that as applied to the carcass beforeevisceration the solution, spray or mist is at a temperature above roomtemperature but not higher than about 70° C., and preferably not higherthan about 39° C. Since such heating does not materially diminish thebiocidal activity of the aqueous microbiocidally-effective compositionsof this invention, the ability to so heat such compositions ensures thatcustomary processing line speeds in automated slaughterhouses will notbe unduly compromised.

When applying an aqueous microbiocidally-effective composition of thisinvention to an animal carcass during hide removal it is convenient toemploy either spraying or misting as the method of application. In thisway the customary hide removal operation need not be materially alteredin order to accommodate the application of the aqueousmicrobiocidally-effective composition of this invention to the carcassduring hide removal.

In one preferred embodiment of the invention a series of spaced-apartsuspended non-eviscerated animal carcasses is passed into a spray zonesuch as one or more cabinets or shower stall areas fitted with nozzlesand/or spray heads that direct at least one spray or shower, preferablya plurality of sprays, of an aqueous microbiocidally-effectivecomposition of this invention onto the surfaces of at least one carcassat a time as it passes through the spray zone. The coverage of thesprays should ensure that the surfaces of the suspended carcass are allexposed to, and come into contact with, the aqueousmicrobiocidally-effective composition of this invention. In thisembodiment the non-eviscerated carcasses entering the spray zone willeither have been skinned (i.e., the hide has been removed) or the hideor skin will remain intact but hair and/or bristles will have beenremoved from the carcass typically by singeing, shearing or othersuitable hair and/or bristle removal technique, the choice betweenskinning and hair and/or bristle removal depending on the kind ofanimals being processed. For example, with cattle the hide willtypically be removed prior to entry of the carcass into the spray zonefor antimicrobial treatment of this invention with an aqueousmicrobiocidally-effective composition of this invention, whereas withswine, the carcass will typically be singed to bum off surface hairand/or bristles prior to entry of the carcass into the spray zone forsuch treatment. After the carcass exits the spray zone, typically thecarcass will be washed with rinse water by any suitable technique suchas dipping, spraying, submerging, etc., and then eviscerated, or will besubjected to evisceration as the next step in the processing without anintervening water wash.

Still another preferred embodiment of the invention involves applying anaqueous microbiocidally-effective composition of this invention to theanimal carcass during evisceration. In order to minimize the possibilityof interfering with the normal or conventional evisceration procedure,it is preferable to apply the aqueous microbiocidally-effectivecomposition of this invention to the carcass as a mist or as alow-pressure fine spray during most if not all of the time the carcassis being eviscerated. Such misting or fine spraying ensures that thecarcass and the entrails are both thoroughly wetted by the aqueousmicrobiocidally-effective composition of this invention without at thesame time impairing the effectiveness of the operation. A particularadvantage of this preferred embodiment is that microbial or bacterialcontamination in the event of rupture of entrails is promptly combatedby the presence and continuous application of the highly effectiveaqueous microbiocidal composition of this invention. As a consequence,contamination of ensuing carcasses by such microbial or bacterialcontamination can be avoided without shutting the line down. As anadjunct to this preferred embodiment, the entrails after removal can betransported or conveyed to a washing zone where the entrails aresubmerged in a bath of an aqueous microbiocidally-effective compositionof this invention for a period sufficient to ensure effective microbialand bacterial control.

A further embodiment of this invention is to conduct an inside-outsidecarcass washing of the eviscerated carcass prior to and/or during and/orafter the carcass splitting operation. In conducting such inside-outsidecarcass washing pursuant to this invention, it is preferred to use aspray delivery system such as a probe or bayonet which, pursuant to thisinvention, applies a pressurized spray of the aqueousmicrobiocidally-effective composition of this invention to the interiorcavity of the carcass and another spray delivery system such as a seriesof nozzles, which system applies the aqueous microbiocidally-effectivecomposition of this invention to the exterior of the carcass. Inparticularly preferred embodiments of this invention the aqueousmicrobiocidally-effective composition of this invention applied by thespray delivery system to the interior cavity of the carcass has a higherconcentration of microbiocide formed fromN,N′-bromochloro-5,5-dialkylhydantoin(s) than the concentration of themicrobiocide formed from the N,N′-bromochloro-5,5-dialkylhydantoin(s) inthe water applied by the spray delivery system to the exterior thecarcass. The N,N′-bromochloro-5,5-dialkylhydantoin(s) used for formingthe microbiocidal content in the water used for washing the interiorcavity of the carcass and the N,N′-bromochloro-5,5-dialkylhydantoin(s)used for forming the microbiocidal content of the water used for washingthe exterior of the carcass can be, and usually will be, of the samechemical composition. However, N,N′-bromochloro-5,5-dialkylhydantoin(s)of different chemical composition can be used for forming theserespective aqueous microbiocidally-effective compositions of thisinvention for such inside-outside washing.

In another preferred embodiment of the invention a plurality ofsuspended eviscerated animal carcasses as they are being conveyed orotherwise transported into a cooling zone and/or after they have beenreceived in a cooling zone are subjected while still warm (i.e., thecarcasses have not lost all of the original body heat of the animalwhile alive) to at least one spray, shower, or mist of an aqueousmicrobiocidally-effective composition of this invention so that suchcomposition comes into contact with both the inside and the outside ofthe carcass. When the suspended carcass is being transported toward thecooling zone, the spraying, showering, or misting of the travelingcarcass can be effected within one or more suitable spray or mistingcabinets or within one or more shower stalls or shower zones.Optionally, rinse water may be applied after application of the aqueousmicrobiocidally-effective composition of this invention. When thecarcass is within the cooling zone, typically in a stationary fixed orrotatable position, such spraying, showering, or misting can beconducted continuously for a single suitable period of time, butpreferably such sprays, showers, or mists can be periodically applied tothe carcass. This preferred embodiment is particularly advantageous foruse in the processing of cattle where carcasses are typically aged in acooling zone for periods in the range of about 6 to about 48 hours. Theapplication of such sprays, showers, or mists, especially if conductedperiodically during the aging period, not only effectively preventsmicrobial development and growth, but keeps the meat from losingtenderness. In sharp contrast, application of a spray, shower, or mistof plain water during aging in a cooling zone in order to keep the meatfrom drying out and becoming tough, tends to result in an explosivegrowth of bacterial population.

Another feature of this invention is that the suspended evisceratedanimal carcasses as they are being conveyed or otherwise transportedinto a cooling zone and/or after they have been received in a coolingzone can be sprayed, showered, or misted with an aqueousmicrobiocidally-effective composition of this invention that is itselfat a low temperature of about 15° C. or below and preferably at about10° C. or below, and more preferably at a temperature at about 7° C. orbelow, but in all cases above the freezing temperature of themicrobiocidal solution. It can be seen therefore that in this operationthe cold spray, shower, or mist used serves several functions. First ofall, the cold spray, shower, or mist applied to these carcasses providesexcellent microbial and/or bacterial control even though used at suchlow temperatures. Secondly the cold spray, shower, or mist when appliedto the carcasses as they are being conveyed or otherwise transportedinto a cooling zone and/or shortly after they have been received in acooling zone assists in chilling the carcasses. Thirdly, the cold spray,shower, or mist when applied to the carcasses that have already beenchilled sufficiently so as to be at the desired low temperature, willnot materially increase the temperature of the chilled carcasses. In allcases the coverage of the sprays, showers, or mists should ensure thatthe surfaces of the suspended carcass are exposed to the aqueousmicrobiocidally-effective composition of this invention.

Pursuant to another preferred embodiment of this invention, effectivemicrobiocidal control in the processing of four-legged slaughteranimals, especially cattle or swine, is brought about by use of anaqueous microbiocidally-effective composition of this invention in atleast two of three important animal processing stages or stations,whereby without materially affecting productivity, more effectivemicrobiocidal control is achieved as compared to use of hypochlorite orvarious other chlorine-derived microbiocides.

More particularly, pursuant to this preferred embodiment of thisinvention water treated with at least oneN,N′-bromochloro-5,5-dialkylhydantoin to form an aqueousmicrobiocidally-effective composition of this invention is brought intocontact with the carcass of a four-legged slaughter animal during atleast two of the following three operations: (1) before, during and/orafter hide removal or before and/or after hair and/or bristle removal,and in some cases during hair and/or bristle removal by methods otherthan singeing, (2) during evisceration, and (3) immediately prior toand/or during chilling. Methods for carrying out each of these threeoperations have been described hereinabove.

In a particularly preferred embodiment, an aqueousmicrobiocidally-effective composition of this invention is utilized inat least two, preferably at least three, more preferably at least four,and most preferably in at least five of the following operations for astate-of-the-art slaughter house in the processing of cattle: (1) hideremoval, (2) disinfection between hide removal and prior toevisceration, (3) evisceration, (4) carcass splitting, (5) final wash,and (6) chill. Operations other than (2) are typically carried out instate-of-the-art slaughterhouses in the processing of cattle, but ofcourse without using an aqueous microbiocidally-effective composition ofthis invention in any operation. Operation (2) is an operation believedto be unique to this invention. Methods for carrying out operations (1),(2), (3), (4), and (6) in accordance with this invention have beendescribed hereinabove. In operation (5), i.e., the final wash operation,any conventional way of carrying out such an operation can be usedpursuant to this invention simply by including in some or all of thewash water an aqueous microbiocidally-effective composition of thisinvention.

In another particularly preferred embodiment, an aqueousmicrobiocidally-effective composition of this invention is utilized inat least two, preferably at least three, and most preferably in all fourof the following operations: utilized in a state-of-the-art slaughterhouse in the processing of swine: (1) disinfection between hair and/orbristle and/or skin removal and prior to evisceration, (2) evisceration,(3) splitting, and (4) chill. Operations other than (1) are typicallycarried out in state-of-the-art slaughterhouses in the processing ofswine, but of course without using an aqueous microbiocidally-effectivecomposition of this invention in any operation. Operation (1) is anoperation believed to be unique to this invention. Methods for carryingout operations (1), (2), (3), and (4) in accordance with this inventionhave been described hereinabove.

In conducting spraying operations pursuant to this invention in one ormore of the various stages or locations in an animal carcass processingline, the nozzles used for applying the aqueousmicrobiocidally-effective composition of this invention to the animalcarcass can be fixed or articulating nozzles. In addition, duringspraying, showering or misting steps used in the practice of thisinvention, rotary brushes or other ways of increasing contact betweenthe aqueous microbiocidally-effective composition of this invention andthe carcass, such as use of ultrasonic energy, can be used. Thereafterthe carcass can be rinsed with clear water, if deemed necessary ordesirable. Such rinsing water can be fresh or recirculated water, or acombination of both. The recirculated water should be effectively purgedof residual impurities from prior usage.

It is possible pursuant to a further embodiment of this invention tominimize the amount of waste water generated in carrying out variousembodiments of this invention. For example, in a system wherein aplurality of individual suspended carcasses are transported through theprocessing line having various processing stations, at least one givenstation is provided with at least one suitably-positioned motion sensoror detector operatively associated with apparatus to start and stop theflow of aqueous microbiocidally-effective composition of this inventionto that station of the line. When the sensor detects that a carcass isentering a specified zone in that station where the spray, shower, ormist is to be applied to the carcass, the sensor sends a signal to thestart-stop apparatus which turns on the flow of aqueousmicrobiocidally-effective composition of this invention. This flow canbe maintained and then shut off by the system in various ways. One wayis for the flow to last for a specified time period coordinated with thetravel rate of carcasses through the line at that station so that aftera sufficient time period during which a predetermined amount of spray,shower, or mist has been applied to the carcass, the flow of spray,shower, or mist is automatically stopped.

Another way is to automatically cut off the flow after a predeterminedthe volume of liquid flow has been sent to the spray, shower, or mistingdevices. Still another way is for another motion sensor or detector tosense when the carcass has advanced to a second position in that stationand thereupon to signal the start-stop apparatus to turn off the flow.The motion sensors or detectors can be positioned to sense the presenceof the carcass itself. Alternatively they can be positioned to sense thepresence of a suitable portion of the carcass transporting system suchas the traveling carrier for the carcass suspension mechanism, or thecarcass suspension mechanism or a portion thereof such as the wire,cable, chain, shackle, or hook that is holding the suspended carcass.

Suitable motion sensing or detection devices known in the art can beadapted for use in the above waste water minimization embodiment of thisinvention. The so-called electric eye that senses the presence of aperson entering an elevator and causes the elevator doors to remain openor to retract the doors serves as a commonly encountered sensing device.Various other devices are known. See for example U.S. Pat. No.6,623,348.

In the practice of this invention in Type II operations, the aqueousmicrobiocidally-effective composition of this invention can be appliedbefore and/or during making incisions in the carcass for the purpose ofinspection as well as for eviseration.

Type III Processing

This type of processing pursuant to this invention comprises contactingraw meat products and/or processed meat products derived from theslaughtered animal(s), with an aqueous microbiocidal composition formedby mixing at least one N,N′-bromochloro-5,5-dialkylhydantoin with anaqueous medium to form an aqueous microbiocidally-effective composition.This contacting should occur at one or more suitable stages before,during and/or after the formation or preparation of such raw meat and/ormeat products. The methods of applying an aqueousmicrobiocidally-effective composition of this invention to the raw meatand/or meat products are much the same as described above. Thusspraying, dipping, bathing, showering or like operations can be used.Also, in small slaughter houses or meat packing plants, hand-heldsponges or washing cloths may be used for applying the aqueousmicrobiocidally-effective composition of this invention. The raw meatproducts and/or processed meat products or precursors thereof, can beconveyed by automated conveying equipment such as conveyor belts onwhich such products or precursors are carried and transported, or movingtracks, belts, or cables by which such products or precursors aresuspended, carried, and transported.

The raw meat that can be contacted with an aqueousmicrobiocidally-effective composition of this invention can be in anyform typically derived from the animal carcass. Non-limiting examples ofsuch raw meat products include (a) meat cuts as for example steaks,chops, rib sections, meat roast cuts, hams, loins, bacon, trims, andother similar cuts, (b) animal organs such as liver, kidney, tripe,chitlins, tongue, and other organs or organ parts, and (c) ground rawmeat such as ground beef, ground pork, raw meat sausages, and the like.Non-limiting examples of processed meat products that can be contactedwith an aqueous microbiocidally-effective composition of this inventioninclude ready-to-eat deli products, sausages, frankfurters, slicedmeats, jerky, and/or other processed meat products.

Preferred raw meat products to which an aqueousmicrobiocidally-effective composition of this invention is appliedinclude red meat, red meat parts, white meat, and white meat parts. Mostpreferred is the application of an aqueous microbiocidally-effectivecomposition of this invention to raw red meat (beef) from cattle or toraw white meat (pork) from swine.

In Type III processing, the aqueous microbiocidally-effectivecomposition of this invention used will be a composition formed bymixing water and at least one N,N′-bromochloro-5,5-dialkylhydantoinmicrobiocidal agent in an amount in the range of about 0.5 to about 400ppm (wt/wt) as free bromine. The particular concentration of the one ormore N,N′-bromochloro-5,5-dialkylhydantoins used in forming suchcompositions, will vary depending upon the particular raw meat productand/or processed meat product being produced. In many cases such as inthe treatment of raw meat cuts and ground or sliced meat products, theconcentration of the N,N′-bromochloro-5,5-dialkylhydantoin microbiocidalagent used in forming the composition used, will be at the lower end ofthis range; for example, in the range of about 0.5 to about 100 ppm(wt/wt) as free bromine and in some case as low as in the range of about0.5 to about 50 ppm (wt/wt) as free bromine.

Reference to the Drawings

The block diagrams of FIGS. 1 and 2 serve to illustrate, but not tolimit, the invention as applied to cattle and swine, respectively. Asseen from the cattle processing stages depicted in FIG. 1, and the swineprocessing stages depicted in FIG. 2, there are a series of stages whichtypically can be used in a large state of the art slaughter house ormeat packing plant. It is to be understood and appreciated that some ofthe stages depicted can be combined with one or more other stages andthat some of the stages may be eliminated. Moreover, some of the stagesdepicted can be carried out in a different sequence from that depicted.Nevertheless, FIGS. 1 and 2 are deemed to illustrate at least some ofthe ways by which the present invention can be practiced with respect tolive animals and their carcasses after slaughter. To a limited extent,the processing of raw meat products pursuant to this invention can alsobe appreciated from these drawings.

Turning now to FIG. 1, the numerals represent typical stages at whichpursuant to this invention, the live animal, carcass, or parts thereofcan be contacted with an aqueous microbiocidally-effective compositionof this invention. Thus, such contacting can be carried out as at 10during the receipt and holding of cattle, and/or during travel of thelive animal to stunning as at 12, and/or during stunning as at 14,and/or during transport of the stunned live animal to exsanguination asat 16. Such contacting can also be carried out at any one or more of thefollowing stages: before head and shank removal as at 18, and/or duringhead and shank removal as at 20, and/or before hide removal as at 22,and/or during hide removal as at 24, and/or before eviseration as at 26,and/or during eviseration as at 28. At this point of the processing, oneof two commonly-used approaches can be utilized. In one approach, thecontacting pursuant to this invention can occur at one or more of thefollowing stages: before trimming and carcass washing as at 30A, and/orduring trimming and carcass washing as at 32, and/or before cutting andboning as at 34, and/or during cutting and boning as at 36, and/orbefore chilling and cold storage as at 38, and/or during chilling andcold storage as at 40. In the second approach, the contacting pursuantto this invention can occur at one or more of the following stages:before chilling as at 30B, and/or during chilling as at 42, and/orbefore cutting and boning as at 44, and/or during cutting and boning asat 46, and/or before cold storage as at 48, and/or during cold storageas at 50. It will be noted that pursuant to this invention thecontacting as depicted in FIG. 1 can occur at any one or more of thedepicted stages except for during exsanguination. This represents apreference inasmuch as the contacting during exsanguination would tendto dilute the blood released from the animal. However, pursuant to thisinvention, it is possible to carry out the contacting duringexsanguination.

FIG. 2 illustrates in a manner similar to FIG. 1 stages during theprocessing of swine at which the live animal, carcass, or parts thereofcan be contacted with an aqueous microbiocidally-effective compositionof this invention. Thus, such contacting can be carried out as at 11during the receipt and holding of swine, and/or during travel of thelive animal to stunning as at 13, and/or during stunning as at 15,and/or during transport of the stunned live animal to exsanguination asat 17. Such contacting can also be carried out at any one or more of thefollowing stages: before scalding as at 19, and/or during scalding as at21, and/or before dehairing as at 23, and/or during dehairing as at 25,and/or before singeing as at 27, and/or before scraping and polishing asat 29, and/or during scraping and polishing as at 31, and/or beforeeviseration as at 33, and/or during eviseration as at 35, and/or beforecarcass splitting as at 37, and/or during carcass splitting as at 39,and/or before carcass chilling as at 41, and/or during carcass chillingas at 43, and/or before cutting and boning as at 45, and/or duringcutting and boning as at 47, and/or before cold storage as at 49, and/orduring cold storage as at 51. It will be seen that pursuant to thisinvention the contacting as depicted in FIG. 2 can occur at any one ormore of the depicted stages except for during exsanguination and duringsingeing. The avoidance of contacting during exsanguination represents apreference inasmuch as the contacting during exsanguination would tendto dilute the blood released from the animal. However, pursuant to thisinvention, it is possible to carry out the contacting duringexsanguination. In addition, the avoidance of contacting during singeingrepresents another preference as the application of an aqueous solutionto the carcass during singeing would not be conducive to the ordinaryconditions used for conducting a singeing operation. However, ifsingeing conditions can be devised so that the presence of an aqueoussolution would not unduly interfere with such a singeing operation, thecontacting pursuant to this invention can, under such circumstances, beutilized.

Other Considerations

As seen from the above, one or more aqueous microbiocidally-effectivecompositions of this invention are used to effectively control microbialand bacterial contamination of live four-legged slaughter animals,four-legged slaughter animal carcasses, and/or raw meat products and/orprocessed meat products derived from four-legged slaughter animalcarcasses in one or more specified locations in an animal slaughterhouse or meat packing plant. Such aqueous microbiocidally-effectivecompositions of this invention are formed by dissolving one or moreN,N′-bromochloro-5,5-dialkylhydantoins in water. Preferred areN,N′-bromochloro-5,5-dialkylhydantoins in which one of the alkyl groupsis a methyl group and the other alkyl group contains in the range of 1to about 4 carbon atoms. Thus these preferred biocides compriseN,N′-bromochloro-5,5-dimethylhydantoin,N,N′-bromochloro-5-ethyl-5-methylhydantoin,N,N′-bromochloro-5-n-propyl-5-methylhydantoin,N,N′-bromochloro-5-isopropyl-5-methylhydantoin,N,N′-bromochloro-5-n-butyl-5-methylhydantoin,N,N′-bromochloro-5-isobutyl-5-methylhydantoin,N,N′-bromochloro-5-sec-butyl-5-methylhydantoin,N,N′-bromochloro-5-tert-butyl-5-methylhydantoin, and mixtures of any twoor more of them. Of these biocidal agents,N,N′-bromochloro-5-isobutyl-5-methylhydantoin,N,N′-bromochloro-5-n-propyl-5-methylhydantoin, andN,N′-bromochloro-5-ethyl-5-methylhydantoin are, respectively, preferred,more preferred, and even more preferred members of this group from thecost effectiveness standpoint. Of the mixtures of the foregoing biocidesthat can be used pursuant to this invention, it is preferred to useN,N′-bromochloro-5,5-dimethylhydantoin as one of the components, with amixture of N,N′-bromochloro-5,5-dimethylhydantoin andN,N′-bromochloro-5-ethyl-5-methylhydantoin being particularly preferred.The most preferred member of this group of microbiocides isN,N′-bromochloro-5,5-dimethylhydantoin.N,N′-bromochloro-5,5-dimethylhydantoin is available commercially underthe trade designation Bromicide® biocide (Chemtura). Another suitablebromochlorohydantoin mixture is composed predominantly ofN,N′-bromochloro-5,5-dimethylhydantoin (60.0%) together with minorproportions by weight of 1,3-dichloro-5-ethyl-5-methylhydantoin (10.6%)and 1,3-dichloro-5,5-dimethylhydantoin (27.4%). A mixture of this lattertype is available in the marketplace under the trade designationDantobrom® biocide (Lonza Group Ltd.). When a mixture of two or more ofthe foregoing N,N′-bromochloro-5,5-dialkylhydantoin biocides is usedpursuant to this invention, the individual biocides of the mixture canbe in any proportions relative to each other. Minor proportions ofmono-N-bromo-5,5-dialkylhydantoin(s) can be present along with theN,N′-bromochloro-5,5-dialkylhydantoin(s) but such compositions are notpreferred.

It will be understood that the designation N,N′ in reference to, say,N,N′-bromochloro-5,5-dimethylhydantoin means that this compound can be(1) 1-bromo-3-chloro-5,5-dimethylhydantoin, or (2)1-chloro-3-bromo-5,5-dimethylhydantoin, or (3) a mixture of1-bromo-3-chloro-5,5-dimethylhydantoin and1-chloro-3-bromo-5,5-dimethylhydantoin.

Methods for producing N,N′-bromochloro-5,5-dialkylhydantoins are knownand reported in the literature. An especially preferred method isdescribed in WO 01/53270 published 26 Jul. 2001.

The N,N′-bromochloro-5,5-dialkylhydantoin(s) used pursuant to thisinvention can be blended directly in the water to be used in the variousstages or locations referred to herein. For this purpose suitabledispensing devices and methods—including, but not limited to, the deviceand method disclosed in US 2003/0077365—can be employed that meter intowater flowing through the device suitable amounts of theN,N′-bromochloro-5,5-dialkylhydantoin(s) microbiocides. Alternatively,predetermined quantities of micronizedN,N′-bromochloro-5,5-dialkylhydantoin(s) may be added to water inamounts in excess of the final use level, and the resultant concentratecan be further diluted, preferably with agitation, with one or moredifferent amounts of water to form one or more treated watercompositions to be used in the respective stages of the process.

Other additives can be used in conjunction with theN,N′-bromochloro-5,5-dialkylhydantoin(s) provided the other additive oradditives are non-toxic, are compatible with aqueous microbiocidalsolutions formed by dissolving theN,N′-bromochloro-5,5-dialkylhydantoin(s) in water to form the treatedwater used pursuant to this invention, and do not otherwise detract fromthe microbiocidal effectiveness of the treated water in any appreciablemanner. By “in conjunction with” is meant that in most cases the otheradditive component(s) are fed separately into the water being used;e.g., the other additives, if susceptible to oxidation by commonoxidants, are not mixed directly with the undissolvedN,N′-bromochloro-5,5-dialkylhydantoin(s). In general, additives whichare compatible with aqueous hypohalite bleach solutions such as certainradical scavengers, chelating agents, pH buffering agents, surfactants,detergents, and polymers described in detail, for example, in U.S. Pat.No. 6,506,718 or other published literature on the subject may be used,if desired. Generally, desirable additives are not susceptible tooxidation by N,N′-bromochloro-5,5-dialkylhydantoin. It is also possibleto use one or more wetting agents, hydrotropes, thickeners, foamingagents, defoaming agents, buffering agents, acids, bases, demulcents,humectants, emollients, vitamins, and similar functional additives thatmeet the above criteria. Non-limiting examples of such additivesinclude: dioctyl sodium sulfosuccinate (Aerosol OT); dialkylsulfosuccinate; poly(oxyethylene)(20)-sorbitane monooleate (Tween 80);sodium bicarbonate; carbon dioxide; glycerin; and fatty acids (e.g.,lauric acid). In the case of vitamins, the amount or amounts used shouldbe less than a non-skin irritating amount, e.g., less than 50,000international units. If used, the amount of each suitable selectedadditive to be used in conjunction with theN,N′-bromochloro-5,5-dialkylhydantoin(s) should be sufficient to providethe property for which it is employed. Recommendations frommanufacturers of such other additives are useful as guidelines in thisrespect.

Preferably the one N,N′-bromochloro-5,5-dialkylhydantoin or the morethan one N,N′-bromochloro-5,5-dialkylhydantoin is the sole originatingsource of microbiocidal activity in the aqueous medium treatedtherewith. However this invention includes use in the above operationsof aqueous media treated with (A) at least oneN,N′-bromochloro-5,5-dialkylhydantoin and (B) at least one othermicrobiocidal agent which produce a suitably stable compatible aqueousmicrobiocidal composition. In other words, the solution products of (A)and (B) should be compatible with each other in the aqueous medium whenpresent in the amounts and proportions that provide an aqueousmicrobiocidal composition.

The contacting or washing operations when used pursuant to thisinvention ensure that pathogens such as species of Listeria,Escherichia, Salmonella, Campylobacter, and others, are effectivelycontrolled, if not essentially eliminated from the meat product.Moreover, in large scale four-legged slaughter animal processing lineswhere high throughput is essential, the microbiocide of this inventionused in these stages or stations is so effective that it is notnecessary to slow down the line to give the microbiocide time to act.Thus the processing lines can be operated at conventional speeds, if notat increased speeds. Further, the waters used in the respective stagesor stations can each be treated with suitable microbiocidal quantitiesof a given N,N′-bromochloro-5,5-dialkylhydantoin microbiocidal agent,and thus it is possible to use only one such agent throughout the plant,thus simplifying the purchasing, storage and inventory aspects of theplant operation. Indeed it is possible to use water containing the samemicrobiocidal concentration (i.e., the same bromine residual resultingfrom dissolving in water a given amount one or moreN,N′-bromochloro-5,5-dialkylhydantoins) in the water going to each ofmultiple stages or locations in the embodiments of this invention wherean aqueous microbiocidally-effective composition of this invention isused at more than one stage or location in a processing line.

In the practice of various embodiments of this invention, aqueouswashing solutions can be used after, but especially before applying theaqueous microbiocidally-effective composition of this invention to thelive animal, animal carcass, the raw meat product, and/or the processedmeat product. Such aqueous washing solutions can contain any of avariety of useful additional components such as for example sodiumchloride, sodium hydroxide, potassium sorbate, sodium bisulfate, lacticacid, sodium metasilicate, acidified sodium chlorite, polypeptideantibiotic such as nisin, or other known components serving similarfunctions.

The animal carcass, raw meat product, and/or the processed meat productafter contacting with an aqueous microbiocidally-effective compositionof this invention and optionally a subsequent washing solution, can besubjected to additional sanitizing operations. Thus, in accordance withanother embodiment of this invention, there is provided a method ofprocessing the carcass of a four-legged slaughter animal and/or raw meatproduct derived from said carcass, and/or processed meat product derivedfrom said carcass, which method comprises (a) contacting said carcass,raw meat product derived from said carcass, and/or processed meatproduct derived from said carcass at least once with a microbiocidalsolution formed from mixing together at least (i) water and (ii) atleast one N,N′-bromochloro-5,5-dialkylhydantoin, and (b) subjecting theresultant carcass, raw meat product derived from said carcass, and/orprocessed meat product derived from said carcass to at least onedecontamination process selected from ionizing radiation, UV radiation,microwaves, pulsed light, electric fields, hydrostatic pressure,sonication, infra-red radiation, ozonization, and ozone washing. Steps(a) and (b) can be carried out in any sequence and/or concurrently.

Suitable methods for determining “bromine residual” are known andreported in the literature. See for example, Standard Methods For theExamination of Water and Wastewater, 18th Edition, 1992, from AmericanPublic Health Association, 1015 Fifteenth Street, NW, Washington, DC20005 (ISBN 0-87553-207-1), pages 4-36 and 4-37; Hach Water AnalysisHandbook, Third Edition, 1997, by Hach Company, Loveland Colo.,especially pages 1206 and 1207; and Handbook of Industrial WaterConditioning, 7th edition, Betz Laboratories, Inc., Trevose, Pa. 19047(Library of Congress Catalog Card Number: 76-27257), 1976, pages 24-29.While these references typically refer to “chlorine residual”, the sametechniques are used for determining “bromine residual”, by taking intoaccount the higher atomic weight of bromine as compared to chlorine.

The term “bromine residual” refers to the amount of oxidizing speciespresent in the treated water available for disinfection. Residuals canbe determined as either “free” or “total” depending upon the analyticaltest method employed. In the present case, the numerical values forbromine residual have been given herein on a free bromine basis. Suchvalues can be monitored by use of the analytical procedure for “freechlorine” given below. However if desired, the bromine residual could bemonitored on a “total bromine” basis by using the analytical procedurefor “total chlorine,” designated as Method 8167 in Hach Water AnalysisHandbook, 3rd ed., copyright 1997. In either case the numerical valuesobtained are in terms of chlorine and thus such values are multiplied by2.25 to obtain the corresponding bromine values. Typically the values ona “total bromine” basis on a given sample will be higher than the valueson a “free bromine” basis on the same given sample. The important pointto understand is that this invention relates to the bromine residualthat is actually present in the treated aqueous medium whether the valueis determined by use of the free chlorine test procedure or the totalchlorine test procedure, but use of the free chlorine test procedure isrecommended.

A standard test for determination of low levels of active halogen isknown as the DPD test and is based on classical test procedures devisedby Palin in 1974. See A. T. Palin, “Analytical Control of WaterDisinfection With Special Reference to Differential DPD Methods ForChlorine, Chlorine Dioxide, Bromine, Iodine and Ozone,” J. Inst. WaterEng., 1974, 28, 139. While there are various modernized versions of thePalin procedures, the recommended version of the test is fully describedin Hach Water Analysis Handbook. The procedure for “free chlorine”(i.e., active chlorine) is identified in that publication as Method8021. Briefly, the “free chlorine” test involves introducing to thedilute water sample containing active halogen, a powder comprising DPDindicator powder, (i.e., N,N-diethylparaphenylenediamine, and a buffer).The active halogen species present react(s) with DPD to turn the DPDindicator to red/pink.

In greater detail, the DPD test procedure is as follows:

-   1. To determine the amount of species present in the water which    respond to the “free chlorine” test, the water sample should be    analyzed within a few minutes of being taken, and preferably    immediately upon being taken.-   2. Hach Method 8021 is a test for the amount of species present in a    water sample that respond to the “free chlorine” test. This test    involves the use of the Hach Model DR 2010 calorimeter. The stored    program number for chlorine determinations is recalled by keying in    “80” on the keyboard, followed by setting the absorbance wavelength    to 530 nm by rotating the dial on the side of the instrument. Two    identical sample cells are filled to the 10 mL mark with the water    under investigation. One of the cells is arbitrarily chosen to be    the blank. The blank sample cell is admitted to the sample    compartment of the Hach Model DR 2010, and the shield is closed to    prevent stray light effects. Then the ZERO key is depressed. After a    few seconds, the display registers 0.00 mg/L Cl₂. Then, the blank    sample cell used to zero the instrument is removed from the cell    compartment of the Hach Model DR 2010. To the second cell, the    contents of a DPD Free Chlorine Powder Pillow are added. This is    shaken for 10-20 seconds to mix, as the development of a pink-red    color indicates the presence of species in the water which respond    positively to the DPD “free chlorine” test reagent. Immediately    (within one minute of reagent addition) place the prepared sample    into the cell holder. The light shield is then closed as was done    for the blank, and the READ key is depressed. The result, in mg/L    Cl₂ is shown on the display within a few seconds. This is the “free    chlorine” level of the water sample under investigation. It is to be    noted that the test sample may need to be diluted with halogen    demand free water in order for the chlorine measurement to be within    the measuring range of the instrument. The dilution will need to be    taken into account when determining the chlorine level of the    sample.

The following Example presents test results illustrating one of theimportant advantages accruing from the practice of this invention. ThisExample is presented for purposes of illustration and is not intended tolimit the generic scope of the invention.

EXAMPLE

The effects of various biocides on contact with boneless beef top roundLondon broil were studied experimentally. In a 80×40 crystallizationdish, approximately 25 g of this meat cut was placed. Approximately 30 gof the biocide solution was applied for 5 minutes. This volume ofsolution partially immersed the meat in the solution. After 5 minutesthe meat portion was removed from the biocide solution, rinsed withdeionized water and patted dry. The control was another piece of thesame meat cut placed in deionized water for 5 minutes under the sameconditions given above. The biocidal materials tested were:

-   a) Commercial Lasso household bleach solution;-   b) Commercial chlorine bleach solution containing ca. 100 ppm as    Cl₂;-   c) 2% Lactic acid;-   d) DBDMH, approximately 100 ppm expressed as bromine;-   e) BCDMH, approximately 100 ppm expressed as bromine;-   f) Stabrom 909 biocide (Albemarle Corporation), approximately 100    ppm expressed as bromine.

The results obtained in these tests are summarized in the followingtable. TABLE Test Composition Observations Control Test No change in redcolor a) Commercial Lasso household Brown coloration on surface ofbleach solution the meat b) Commercial chlorine bleach Brown colorationdarker than solution containing ca. control 100 ppm as Cl₂ c) 2% Lacticacid Some browning occurred on sides of the meat with the face slightlylighter than control d) DBDMH, approximately 100 More red than thecontrol ppm expressed as bromine e) BCDMH, approximately 100 Lighterthan the control ppm expressed as bromine f) Stabrom 909 biocide,Lighter than the control approximately 100 ppm expressed as bromineIt was concluded that the development of brown color is clearlyundesirable from a consumer acceptability viewpoint.

Other embodiments of the invention are:

-   AA) A method of processing a four-legged slaughter animal for    consumption as meat and/or meat product(s), said method comprising:    -   a. contacting exterior surfaces of the animal while it is alive        at least once with a microbiocidal solution formed from mixing        together at least (i) water and (ii) at least one        N,N′-bromochloro-5,5-dialkylhydantoin, said contacting occurring        at least once when the animal is en route to being slaughtered        but before the animal is killed by exsanguination; or    -   b. contacting a carcass of said animal, after exsanguination,        with a microbiocidal solution formed from mixing together at        least (i) water and (ii) at least one        N,N′-bromochloro-5,5-dialkylhydantoin; or    -   c. contacting at least one raw meat product and/or at least one        processed meat product derived from said carcass at least once        with a microbiocidal solution formed from mixing together at        least (i) water and (ii) at least one        N,N′-bromochloro-5,5-dialkylhydantoin; or    -   d. conducting any two or all three of a), b), and c).-   AB) A method as in AA) wherein at least a) is conducted.-   AC) A method as in AA) wherein at least b) is conducted.-   AD) A method as in AA) wherein at least c) is conducted.-   AE) A method as in AA) wherein any two or all three of a), b),    and c) are conducted.-   AF) A method as in AA) wherein at least a) is conducted, and wherein    the contacting in a) is conducted at least once outside the    perimeter of a slaughterhouse or meat packing plant.-   AG) A method as in AA) wherein at least a) is conducted, and wherein    the contacting in a) is conducted at least once in an outer    perimeter area of a slaughterhouse or meat packing plant so as to    minimize the extent of microbiocidal contamination reaching the    areas within the slaughterhouse or meat packing plant where animal    carcasses are processed.-   AH) A method as in AA) wherein at least a) is conducted, and wherein    the contacting in a) is conducted at least once in one or more areas    of a slaughterhouse or meat packing plant where processing of live    animals occurs prior to exsanguination so as to minimize the extent    of microbiocidal contamination reaching the one or more areas within    the slaughterhouse or meat packing plant where animal carcasses are    processed subsequent to exsanguination.-   AI) A method as in AA) wherein said microbiocidal solution    additionally contains a non-skin irritating amount of a compound    selected from the group consisting of glycerin, detergents,    surfactants, wetting agents, hydrotropes, thickeners, buffering    agents, acids, bases, demulcents, humectants, emollients, foaming    agents, and defoaming agents, and mixtures thereof.-   AJ) A method as in any of AF)-AI) wherein the contacting in a) is    conducted at least once in a zone through which the animal passes or    is passed while still alive, and in which zone said contacting in a)    is effected by showering and/or spraying external surfaces of said    animal with a microbiocidal solution formed from mixing together at    least (i) water and (ii) at least one    N,N′-bromochloro-5,5-dialkylhydantoin.-   AK) A method as in AJ) wherein said contacting in a) is also    effected by causing the animal to pass, or passing the animal, into    at least one bath of microbiocidal solution formed from mixing    together at least (i) water and (ii) one or more    N,N′-bromochloro-5,5-dialkylhydantoins such that at least the hooves    and lower leg areas of the animal are contacted by said    microbiocidal solution.-   AL) A method as in AK) wherein said animal is caused to pass, or is    passed, into said bath before, during, and/or after the animal    passes, or is passed, through said zone in which said showering    and/or spraying takes place.-   AM) A method as in AK) wherein said animal is caused to pass, or is    passed, into said bath during and/or after the animal passes, or is    passed, through said zone in which said showering and/or spraying    takes place.-   AN) A method as in AK) wherein said animal is caused to pass, or is    passed, into said bath after the animal passes, or is passed,    through said zone in which said showering and/or spraying takes    place.-   AO) A method as in AJ) which is conducted in a portable shower or    spray stall.-   AP) A method as in AK) which is conducted in a portable shower or    spray stall.-   AQ) A method as in any of AA)-AI) wherein said four-legged slaughter    animal is selected from cattle, swine, and sheep.-   AR) A method as in AK) wherein said four-legged slaughter animal is    selected from cattle, swine, and sheep.-   AS) A method as in any of AA)-AI) wherein said at least one    N,N′-bromochloro-5,5-dialkylhydantoin is    N,N′-bromochloro-5,5-dimethylhydantoin.-   AT) A method as in AJ) wherein said at least one    N,N′-bromochloro-5,5-dialkylhydantoin is    N,N′-bromochloro-5,5-dimethylhydantoin.-   AU) A method as in AK) wherein said one or more    N,N′-bromochloro-5,5-dialkylhydantoins comprises    N,N′-bromochloro-5,5-dimethylhydantoin.-   AV) A method as in AL) wherein said one or more    N,N′-bromochloro-5,5-dialkylhydantoins comprises    N,N′-bromochloro-5,5-dimethylhydantoin.-   AW) A method as in AM) wherein said one or more    N,N′-bromochloro-5,5-dialkylhydantoins comprises    N,N′-bromochloro-5,5-dimethylhydantoin.-   AX) A method as in AN) wherein said one or more    N,N′-bromochloro-5,5-dialkylhydantoins comprises    N,N′-bromochloro-5,5-dimethylhydantoin.-   AY) A method as in AO) wherein said at least one    N,N′-bromochloro-5,5-dialkylhydantoin comprises    N,N′-bromochloro-5,5-dimethylhydantoin.-   AZ) A method as in AP) wherein said one or more    N,N′-bromochloro-5,5-dialkylhydantoins comprises    N,N′-bromochloro-5,5-dimethylhydantoin.-   BA) A method as in BQ) wherein said at least one    N,N′-bromochloro-5,5-dialkylhydantoin comprises    N,N′-bromochloro-5,5-dimethylhydantoin.-   BB) A method as in BR) wherein said at least one    N,N′-bromochloro-5,5-dialkylhydantoin comprises    N,N′-bromochloro-5,5-dimethylhydantoin.-   BC) A method as in AC) wherein said four-legged slaughter animal is    selected from cattle, swine, and sheep.-   BD) A method as in AC) wherein said contacting at least is conducted    before, during, and/or after hide removal from the carcass of an    animal from which hide is removed during processing.-   BE) A method as in AC) wherein said contacting at least is conducted    before and/or during hide removal from the carcass of an animal from    which hide is removed during processing.-   BF) A method as in AC) wherein said contacting at least is conducted    before hide removal from the carcass of an animal from which hide is    removed during processing.-   BG) A method as in AC) wherein said contacting at least is conducted    before, during and/or after hair removal from the carcass of an    animal from which hair is removed during processing.-   BH) A method as in AC) wherein said contacting at least is conducted    before, during and/or after skin removal from the carcass of an    animal from which skin is removed during processing.-   BI) A method as in AC) wherein said contacting at least is conducted    before and/or after bristle removal from the carcass of an animal    from which bristles are removed during processing.-   BJ) A method as in AC) wherein said contacting at least is conducted    during bristle removal from the carcass of an animal from which    bristles are removed, during processing, by a method other than    singeing.-   BK) A method as in AC) wherein said animal is selected from steers,    heifers, cows, calves, and bulls, and said contacting at least is    conducted one or more times prior to head and/or shank removal    and/or at least is conducted one or more times during head and/or    shank removal and/or at least is conducted one or more times after    head and/or shank removal.-   BL) A method as in any of BD)-BF) wherein said animal is selected    from steers, heifers, cows, calves, and bulls.-   BM) A method as in BI) or BJ) wherein said animal is selected from    hogs, sows, gilts, barrows, boars and pigs.-   BN) A method as in BC) wherein said animal is selected from steers,    heifers, cows, calves, and bulls, and said contacting at least is    conducted (i) during carcass splitting and/or (ii) one or more times    after carcass splitting.-   BO) A method as in BC) wherein said animal is selected from steers,    heifers, cows, calves, and bulls, and said contacting at least is    conducted (i) during final wash and/or (ii) one or more times after    final wash.-   BP) A method as in BC) wherein said animal is selected from steers,    heifers, cows, calves, and bulls, and said contacting at least is    conducted (i) one or more times during chilling and/or (ii) one or    more times after chilling.-   BQ) A method as in BP) wherein after said chilling said contacting    at least is conducted (i) one or more times during carcass cutting    and boning and/or (ii) one or more times after carcass cutting and    boning.-   BR) A method as in BC) wherein said animal is selected from steers,    heifers, cows, calves, and bulls, and said contacting at least is    conducted one or more times during hot boning.-   BS) A method as in BC) wherein said animal is selected from hogs,    sows, gilts, barrows, boars and pigs, and said contacting at least    is conducted prior to scalding the carcass.-   BT) A method as in BC) wherein said animal is selected from hogs,    sows, gilts, barrows, boars and pigs, and said contacting at least    is conducted during and/or one or more times after dehairing and/or    singeing the carcass.-   BU) A method as in BC) wherein said animal is selected from hogs,    sows, gilts, barrows, boars and pigs, and said contacting at least    is conducted during and/or one or more times after scraping and/or    polishing said carcass.-   BV) A method as in BC) wherein said animal is selected from hogs,    sows, gilts, barrows, boars and pigs, and said contacting at least    is conducted during and/or one or more times after evisceration.-   BW) A method as in BC) wherein said animal is selected from hogs,    sows, gilts, barrows, boars and pigs, and said contacting at least    is conducted during and/or one or more times after final wash.-   BX) A method as in BC) wherein animal is selected from hogs, sows,    gilts, barrows, boars and pigs, and said contacting at least is    conducted one or more times during chilling and/or one or more times    after chilling.-   BY) A method as in BC) wherein said animal is selected from hogs,    sows, gilts, barrows, boars and pigs, and said contacting at least    is conducted during carcass splitting and/or as a next step after    carcass splitting.-   BZ) A method as in BC) wherein said animal is selected from steers,    heifers, cows, calves, bulls, hogs, sows, gilts, barrows, boars and    pigs, and wherein said contacting at least is conducted one or more    times during cutting and boning of a carcass.-   CA) A method as in any of BC)-BK) or BN)-BZ) wherein said at least    one N,N′-bromochloro-5,5-dialkylhydantoin used in forming said    microbiocidal solution is at least one    N,N′-bromochloro-5,5-dialkylhydantoin in which one of the alkyl    groups is a methyl group and the other alkyl group contains in the    range of 1 to about 4 carbon atoms, and wherein said microbiocidal    solution optionally contains a non-skin irritating amount of a    compound selected from the group consisting of glycerin, detergents,    surfactants, wetting agents, hydrotropes, thickeners, buffering    agents, acids, bases, demulcents, humectants, emollients, foaming    agents, defoaming agents, and mixtures thereof.-   CB) A method as in BL) wherein said at least one    N,N′-bromochloro-5,5-dialkylhydantoin used in forming said    microbiocidal solution is at least one    N,N′-bromochloro-5,5-dialkylhydantoin in which one of the alkyl    groups is a methyl group and the other alkyl group contains in the    range of 1 to about 4 carbon atoms, and wherein said microbiocidal    solution optionally contains a non-skin irritating amount of a    compound selected from the group consisting of glycerin, detergents,    surfactants, wetting agents, hydrotropes, thickeners, buffering    agents, acids, bases, demulcents, humectants, emollients, foaming    agents, defoaming agents, and mixtures thereof.-   CC) A method as in BM) wherein said at least one    N,N′-bromochloro-5,5-dialkylhydantoin used in forming said    microbiocidal solution is at least one    N,N′-bromochloro-5,5-dialkylhydantoin in which one of the alkyl    groups is a methyl group and the other alkyl group contains in the    range of 1 to about 4 carbon atoms, and wherein said microbiocidal    solution optionally contains a non-skin irritating amount of a    compound selected from the group consisting of glycerin, detergents,    surfactants, wetting agents, hydrotropes, thickeners, buffering    agents, acids, bases, demulcents, humectants, emollients, foaming    agents, defoaming agents, and mixtures thereof.-   CD) A method as in CA) wherein said at least one    N,N′-bromochloro-5,5-dialkylhydantoin used in forming said    microbiocidal solution is N,N′-bromochloro-5,5-dimethylhydantoin.-   CE) A method as in CB) wherein said at least one    N,N′-bromochloro-5,5-dialkylhydantoin used in forming said    microbiocidal solution is N,N′-bromochloro-5,5-dimethylhydantoin.-   CF) A method as in CC) wherein said at least one    N,N′-bromochloro-5,5-dialkylhydantoin used in forming said    microbiocidal solution is N,N′-bromochloro-5,5-dimethylhydantoin.-   CG) A method as in CA) wherein the microbiocidal solution used in    said contacting has a free bromine residual as Br₂ of about 400 ppm    (wt/wt) or less.-   CH) A method as in CB) wherein the microbiocidal solution used in    said contacting has a free bromine residual as Br₂ of about 400 ppm    (wt/wt) or less.-   CI) A method as in CC) wherein the microbiocidal solution used in    said contacting has a free bromine residual as Br₂ of about 400 ppm    (wt/wt) or less.-   CJ) A method as in D) wherein the microbiocidal solution used in    said contacting has a free bromine residual as Br₂ of about 400 ppm    (wt/wt) or less.-   CK) A method as in CE) wherein the microbiocidal solution used in    said contacting has a free bromine residual as Br₂ of about 400 ppm    (wt/wt) or less.-   CL) A method as in CF) wherein the microbiocidal solution used in    said contacting has a free bromine residual as Br₂ of about 400 ppm    (wt/wt) or less.-   CM) A method as in any of CG-CL) wherein said animal is rinsed with    water within at least five minutes after said contacting.-   CN) A method as CG) wherein said free bromine residual is about 100    ppm (wt/wt) or less.-   CO) A method as CH) wherein said free bromine residual is about 100    ppm (wt/wt) or less.-   CP) A method as CI) wherein said free bromine residual is about 100    ppm (wt/wt) or less.-   CQ) A method as CJ) wherein said free bromine residual is about 100    ppm (wt/wt) or less.-   CR) A method as CK) wherein said free bromine residual is about 100    ppm (wt/wt) or less.-   CS) A method as CL) wherein said free bromine residual is about 100    ppm or less.-   CT) A method as in any of CN-CS) wherein said animal is rinsed with    water within at least five minutes after said contacting.-   CU) A method of processing at least one raw meat product derived    from a carcass of at least one four-legged slaughter animal and/or    at least one processed meat product derived from a carcass of at    least one four-legged slaughter animal, which method comprises    contacting said at least one raw meat product and/or said at least    one processed meat product at least once with a microbiocidal    solution formed from mixing together at least (i) water and (ii) at    least one N,N′-bromochloro-5,5-dialkylhydantoin.-   CV) A method as in CU) wherein said at least one    N,N′-bromochloro-5,5-dialkylhydantoin used in forming said    microbiocidal solution is at least one    N,N′-bromochloro-5,5-dialkylhydantoin in which one of the alkyl    groups is a methyl group and the other alkyl group contains in the    range of 1 to about 4 carbon atoms, and wherein said microbiocidal    solution optionally contains a non-skin irritating amount of a    compound selected from the group consisting of glycerin, detergents,    surfactants, wetting agents, hydrotropes, thickeners, buffering    agents, acids, bases, demulcents, humectants, emollients, foaming    agents, defoaming agents, and mixtures thereof.-   CW) A method as in CU) wherein said at least one    N,N′-bromochloro-5,5-dialkylhydantoin used in forming said    microbiocidal solution is N,N′-bromochloro-5,5-dimethylhydantoin.-   CX) A method as in any of CU-CW) wherein the microbiocidal solution    used in said contacting has a bromine residual as Br₂ of about 400    ppm (wt/wt) or less as free bromine.-   CY) A method as in CX) wherein said bromine residual as Br₂ is in    the range of about 0.5 to about 200 ppm (wt/wt) as free bromine.-   CZ) A method as in CX wherein said bromine residual as Br₂ is in the    range of about 0.5 to about 100 ppm (wt/wt) as free bromine.-   DA) A method as in CX) wherein said bromine residual as Br₂ is in    the range of about 0.5 to about 50 ppm (wt/wt) as free bromine.-   DB) A method as in any of CU)-CW) wherein at least one raw meat    product is subjected to said contacting.-   DC) A method as in DB) wherein said at least one raw meat product is    rinsed with water within at least 5 minutes after said contacting.-   DD) A method as in DC) wherein said at least one raw meat product is    a cut of raw beef which is not darkened by said contacting.-   DE) A method of decreasing microbial contamination of a carcass of a    four-legged slaughter animal, which method comprises at least    contacting said carcass with an aqueous biocidal composition at    least once before, during and/or after removal of hide, hair,    bristles, or skin from the carcass, said composition comprising a    microbiocidally-effective product solution of at least one    N,N′-bromochloro-5,5-dialkylhydantoin and water, and wherein said    composition optionally contains a non-skin irritating amount of a    compound selected from the group consisting of glycerin, detergents,    surfactants, wetting agents, hydrotropes, thickeners, buffering    agents, acids, bases, demulcents, humectants, emollients, foaming    agents, defoaming agents, and mixtures thereof.-   DF) A method as in DE) wherein said contacting directly precedes    removal of the hide, hair, bristles, or skin from said carcass, and    optionally is additionally conducted during and/or after removal of    the hide or skin from said carcass.-   DG) A method as in DE) wherein said contacting is conducted during    removal of the hide, hair, bristles, or skin from said carcass, and    optionally is additionally conducted before and/or after removal of    the hide or skin from said carcass.-   DH) A method as in DE) wherein said contacting is conducted after    removal of the hide, hair, bristles, or skin from said carcass, and    optionally is additionally conducted before and/or during removal of    the hide or skin from said carcass.-   DI) A method as in DE) wherein said contacting is conducted one or    more times but only after removal of the hide, hair, bristles, or    skin from said carcass.-   DJ) A method as in any of AA)-AI) wherein said at least one    N,N′-bromochloro-5,5-dialkylhydantoin used in forming said    microbiocidal solution is at least one    N,N′-bromochloro-5,5-dialkylhydantoin in which one of the alkyl    groups is a methyl group and the other alkyl group contains in the    range of 1 to about 4 carbon atoms.-   DK) A method of processing a carcass of a four-legged slaughter    animal and/or raw meat product derived from said carcass, and/or    processed meat product derived from said carcass, which method    comprises:    -   a. contacting said carcass, raw meat product derived from said        carcass, and/or processed meat product derived from said carcass        at least once with a microbiocidal solution formed from mixing        together at least (i) water and (ii) at least one        N,N′-bromochloro-5,5-dialkylhydantoin;    -   b. subjecting said carcass, raw meat product derived from said        carcass, and/or processed meat product derived from said carcass        to at least one decontamination process selected from ionizing        radiation, UV radiation, microwaves, pulsed light, electric        fields, hydrostatic pressure, sonication, infra-red radiation,        ozonization, and ozone washing; or    -   c. a) and b) being conducted in any sequence and/or        concurrently.-   DL) A method as in DK) wherein said at least one    N,N′-bromochloro-5,5-dialkylhydantoin used in forming said    microbiocidal solution is at least one    N,N′-bromochloro-5,5-dialkylhydantoin in which one of the alkyl    groups is a methyl group and the other alkyl group contains in the    range of 1 to about 4 carbon atoms, and wherein said microbiocidal    solution optionally contains a non-skin irritating amount of a    compound selected from the group consisting of glycerin, detergents,    surfactants, wetting agents, hydrotropes, thickeners, buffering    agents, acids, bases, demulcents, humectants, emollients, foaming    agents, defoaming agents, and mixtures thereof.-   DM) A method as in DK) wherein said at least one    N,N′-bromochloro-5,5-dialkylhydantoin used in forming said    microbiocidal solution is N,N′-bromochloro-5,5-dimethylhydantoin.-   DN) A method as in any of DK)-DK) wherein the microbiocidal solution    used in said contacting has a bromine residual as Br₂ of about 400    ppm (wt/wt) or less as free bromine.-   DO) A method as in DN) wherein said bromine residual as Br₂ is in    the range of about 0.5 to about 200 ppm (wt/wt) as free bromine.-   DP) A method as in DN) wherein said bromine residual as Br₂ is in    the range of about 0.5 to about 100 ppm (wt/wt) as free bromine.-   DQ) A method as in DN) wherein said bromine residual as Br₂ is in    the range of about 0.5 to about 50 ppm (wt/wt) as free bromine.-   DR) A method as in any of CU)-CW) wherein the method is applied to    at least one raw meat product and wherein said raw meat product is    at least one ground raw meat product.-   DS) A method as in DR) wherein said at least one ground raw meat    product is comprised of ground beef.-   DT) A method as in DR) wherein said at least one ground raw meat    product is comprised of ground pork.-   DU) A method as in DR) wherein said at least one ground raw meat    product is comprised of ground raw sausage meat comprised of at    least ground beef and/or ground pork.

One end result achievable by the practice of this invention is thathighly effective minimization of microbiological contamination withinthe slaughterhouse or meat packing plant can be achieved by minimizingthe extent to which microbacterial contamination is brought into theslaughterhouse or meat packing plant by the live animals themselves.Another end result is that highly effective minimization ofmicrobiological contamination of the carcass and meat product can beachieved at each of the stages or locations of the animal carcassprocessing line. In addition, the invention enables the provision of ameat product in which the taste, sensory quality, appearance, andwholesomeness of the product should not be adversely affected in anymaterial manner by the microbiocidal operations conducted pursuant tothis invention. And when properly conducted, this invention makespossible achievement of significantly higher microbial control thanachieved with comparable levels of previously known microbiocides foruse in treatment of animal carcasses, such as hypochlorite in water.

Compounds referred to by chemical name or formula anywhere in thisdocument, whether referred to in the singular or plural, are identifiedas they exist prior to coming into contact with another substancereferred to by chemical name or chemical type (e.g., another component,a solvent, or etc.). It matters not what chemical changes, if any, takeplace in the resulting mixture or solution, as such changes are thenatural result of bringing the specified substances together under theconditions called for pursuant to this disclosure. As an example, thephase “water treated with at least oneN,N′-bromochloro-5,5-dialkylhydantoin” and phrases of similar importsignify that just before being brought into contact with an aqueousmedium such as water, the at least oneN,N′-bromochloro-5,5-dialkylhydantoin referred to was the specifiedN,N′-bromochloro-5,5-dialkylhydantoin. The phrase thus is not intendedto suggest or imply that the chemical exists unchanged in the water. Thetransformations that take place are the natural result of bringing thesesubstances together, and thus need no further elaboration.

Also, even though the claims may refer to substances in the presenttense (e.g., “comprises”, “is”, etc.), the reference is to the substanceas it exists at the time just before it is first contacted, blended ormixed with one or more other substances in accordance with the presentdisclosure.

Except as may be expressly otherwise indicated, the article “a” or “an”if and as used herein is not intended to limit, and should not beconstrued as limiting, the description or a claim to a single element towhich the article refers. Rather, the article “a” or “an” if and as usedherein is intended to cover one or more such elements, unless the textexpressly indicates otherwise.

All documents referred to herein are incorporated herein by reference intoto as if fully set forth in this document.

This invention is susceptible to considerable variation within thespirit and scope of the appended claims.

1. A method of processing a four-legged slaughter animal for consumptionas meat and/or meat product(s), said method comprising: a. contactingexterior surfaces of the animal while it is alive at least once with amicrobiocidal solution formed from mixing together at least (i) waterand (ii) at least one N,N′-bromochloro-5,5-dialkylhydantoin, saidcontacting occurring at least once when the animal is en route to beingslaughtered but before the animal is killed by exsanguination; or b.contacting a carcass of said animal, after exsanguination, with amicrobiocidal solution formed from mixing together at least (i) waterand (ii) at least one N,N′-bromochloro-5,5-dialkylhydantoin; or c.contacting at least one raw meat product and/or at least one processedmeat product derived from said carcass at least once with amicrobiocidal solution formed from mixing together at least (i) waterand (ii) at least one N,N′-bromochloro-5,5-dialkylhydantoin; or d.conducting any two or all three of a), b), and c).
 2. A method as inclaim 1 wherein a) is conducted.
 3. A method as in claim 1 wherein b) isconducted.
 4. A method as in claim 1 wherein c) is conducted.
 5. Amethod as in claim 1 wherein any two or all three of a), b), and c) areconducted.
 6. A method as in claim 2 wherein the contacting is conductedat least once outside the perimeter of a slaughterhouse or meat packingplant.
 7. A method as in claim 2 wherein the contacting is conducted atleast once in an outer perimeter area of a slaughterhouse or meatpacking plant so as to minimize the extent of microbiocidalcontamination reaching the areas within the slaughterhouse or meatpacking plant where animal carcasses are processed.
 8. A method as inclaim 2 wherein the contacting is conducted at least once in one or moreareas of a slaughterhouse or meat packing plant where processing of liveanimals occurs prior to exsanguination so as to minimize the extent ofmicrobiocidal contamination reaching the one or more areas within theslaughterhouse or meat packing plant where animal carcasses areprocessed subsequent to exsanguination.
 9. A method as in claim 1wherein said microbiocidal solution additionally contains a non-skinirritating amount of a compound selected from the group consisting ofglycerin, detergents, surfactants, wetting agents, hydrotropes,thickeners, buffering agents, acids, bases, demulcents, humectants,emollients, foaming agents, and defoaming agents, and mixtures thereof.10. A method as in claim 6 wherein the contacting is conducted at leastonce in a zone through which the animal passes or is passed, and inwhich zone said contacting is effected by showering and/or sprayingexternal surfaces of said animal with said microbiocidal solution.
 11. Amethod as in claim 10 which is conducted in a portable shower or spraystall.
 12. A method as in claim 9 wherein said at least oneN,N′-bromochloro-5,5-dialkylhydantoin isN,N′-bromochloro-5,5-dimethylhydantoin.
 13. A method as in claim 3wherein said four-legged slaughter animal is selected from cattle,swine, and sheep.
 14. A method as in claim 3 wherein said animal isselected from steers, heifers, cows, calves, and bulls, and wherein saidcontacting at least is conducted (i) one or more times during headand/or shank removal and/or is conducted (ii) one or more times afterhead and/or shank removal but before hide removal.
 15. A method as inclaim 3 wherein said animal is selected from steers, heifers, cows,calves, and bulls, and wherein said contacting at least is conducted (i)one or more times during hide removal and/or is conducted (ii) one ormore times after hide removal but before evisceration.
 16. A method asin claim 3 wherein said animal is selected from steers, heifers, cows,calves, and bulls, wherein said method includes a sequence of trimmingand/or carcass washing, cutting and/or boning, and chilling and/or coldstorage, and wherein said contacting at least is conducted (i) one ormore times during trimming and/or carcass washing and/or is conducted(ii) one or more times after trimming and/or carcass washing but beforecutting and/or boning.
 17. A method as in claim 3 wherein said animal isselected from steers, heifers, cows, calves, and bulls, wherein saidmethod includes a sequence of trimming and/or carcass washing, cuttingand/or boning, and chilling and/or cold storage, and wherein saidcontacting at least is conducted (i) one or more times during cuttingand/or boning and/or is conducted (ii) one or more times after cuttingand/or boning but before chilling and/or cold storage.
 18. A method asin claim 3 wherein said animal is selected from steers, heifers, cows,calves, and bulls, wherein said method includes a sequence of trimmingand/or carcass washing, cutting and/or boning, and chilling and/or coldstorage, and wherein said contacting at least is conducted (i) one ormore times during chilling and/or cold storage.
 19. A method as in claim3 wherein said animal is selected from steers, heifers, cows, calves,and bulls, wherein said method includes a sequence of chilling, cuttingand/or boning and cold storage, and wherein said contacting at least isconducted (i) one or more times during chilling and/or is conducted (ii)one or more times after chilling but before cutting and/or boning.
 20. Amethod as in claim 3 wherein said animal is selected from steers,heifers, cows, calves, and bulls, and said contacting at least isconducted (i) during carcass splitting and/or (ii) one or more timesafter carcass splitting but before conducting any other processing step.21. A method as in claim 3 wherein said animal is selected from hogs,sows, gilts, barrows, boars and pigs, and said contacting at least isconducted (i) during and/or one or more times after dehairing and/orsingeing the carcass but before conducting any other processing step.22. A method as in claim 3 wherein said animal is selected from hogs,sows, gilts, barrows, boars and pigs, and said contacting at least isconducted (i) during and/or one or more times after scraping andpolishing the carcass but before conducting any other processing step.23. A method as in claim 3 wherein said animal is selected from hogs,sows, gilts, barrows, boars and pigs, and said contacting at least isconducted (i) during and/or one or more times after splitting thecarcass but before conducting any other processing step.
 24. A method asin claim 3 wherein said animal is selected from hogs, sows, gilts,barrows, boars and pigs, and said contacting at least is conducted (i)during and/or one or more times after chilling the carcass but beforeconducting any other processing step.
 25. A method as in claim 3 whereinsaid animal is selected from hogs, sows, gilts, barrows, boars and pigs,and said contacting at least is conducted (i) during and/or one or moretimes after cutting and/or boning the carcass but before conducting anyother processing step.
 26. A method as in claim 3 wherein said animal isselected from hogs, sows, gilts, barrows, boars and pigs, and saidcontacting at least is conducted during cold storage.
 27. A method as inany of claims 14-26 wherein said at least oneN,N′-bromochloro-5,5-dialkylhydantoin used in forming said microbiocidalsolution is at least one N,N′-bromochloro-5,5-dialkylhydantoin in whichone of the alkyl groups is a methyl group and the other alkyl groupcontains in the range of 1 to about 4 carbon atoms, wherein themicrobiocidal solution used in said contacting has a free bromineresidual as Br₂ of about 400 ppm (wt/wt) or less, wherein saidmicrobiocidal solution optionally contains a non-skin irritating amountof a compound selected from the group consisting of glycerin,detergents, surfactants, wetting agents, hydrotropes, thickeners,buffering agents, acids, bases, demulcents, humectants, emollients,foaming agents, defoaming agents, and mixtures thereof, and wherein saidanimal is rinsed with water at least five minutes after said contacting.28. A method of processing at least one raw meat product derived from acarcass of at least one four-legged slaughter animal and/or at least oneprocessed meat product derived from a carcass of at least onefour-legged slaughter animal, which method comprises contacting said atleast one raw meat product and/or said at least one processed meatproduct at least once with a microbiocidal solution formed from mixingtogether at least (i) water and (ii) at least oneN,N′-bromochloro-5,5-dialkylhydantoin.
 29. A method as in claim 28wherein said at least one N,N′-bromochloro-5,5-dialkylhydantoin used informing said microbiocidal solution is at least oneN,N′-bromochloro-5,5-dialkylhydantoin in which one of the alkyl groupsis a methyl group and the other alkyl group contains in the range of 1to about 4 carbon atoms, and wherein said microbiocidal solutionoptionally contains a compound selected from the group consisting ofglycerin, detergents, surfactants, wetting agents, hydrotropes,thickeners, buffering agents, acids, bases, demulcents, humectants,emollients, foaming agents, defoaming agents, and mixtures thereof. 30.A method as in claim 28 wherein said at least oneN,N′-bromochloro-5,5-dialkylhydantoin used in forming said microbiocidalsolution is N,N′-bromochloro-5,5-dimethylhydantoin.
 31. A method as inany of claims 28-30 wherein the microbiocidal solution used in saidcontacting has a bromine residual as Br₂ of about 400 ppm (wt/wt) orless as free bromine.
 32. A method as in claim 31 wherein said bromineresidual as Br₂ is in the range of about 0.5 to about 200 ppm (wt/wt) asfree bromine.
 33. A method as in claim 31 wherein said bromine residualas Br₂ is in the range of about 0.5 to about 100 ppm (wt/wt) as freebromine.
 34. A method as in claim 31 wherein said bromine residual asBr₂ is in the range of about 0.5 to about 50 ppm (wt/wt) as freebromine.
 35. A method as in any of claims 28-30 wherein at least one rawmeat product is subjected to said contacting and wherein said at leastone raw meat product is rinsed with water within at least 5 minutesafter said contacting.
 36. A method as in claim 35 wherein said at leastone raw meat product is a cut of raw beef which is not darkened by saidcontacting.
 37. A method of processing a carcass of a four-leggedslaughter animal and/or raw meat product derived from said carcass,and/or processed meat product derived from said carcass, which methodcomprises: a. contacting said carcass, raw meat product derived fromsaid carcass, and/or processed meat product derived from said carcass atleast once with a microbiocidal solution formed from mixing together atleast (i) water and (ii) at least oneN,N′-bromochloro-5,5-dialkylhydantoin; b. subjecting said carcass, rawmeat product derived from said carcass, and/or processed meat productderived from said carcass to at least one decontamination processselected from ionizing radiation, UV radiation, microwaves, pulsedlight, electric fields, hydrostatic pressure, sonication, infra-redradiation, ozonization, and ozone washing; or c. a) and b) beingconducted in any sequence and/or concurrently.
 38. A method as in claim37 wherein said at least one N,N′-bromochloro-5,5-dialkylhydantoin usedin forming said microbiocidal solution is at least oneN,N′-bromochloro-5,5-dialkylhydantoin in which one of the alkyl groupsis a methyl group and the other alkyl group contains in the range of 1to about 4 carbon atoms, and wherein said microbiocidal solutionoptionally contains a compound selected from the group consisting ofglycerin, detergents, surfactants, wetting agents, hydrotropes,thickeners, buffering agents, acids, bases, demulcents, humectants,emollients, foaming agents, defoaming agents, and mixtures thereof. 39.A method as in claim 37 wherein said at least oneN,N′-bromochloro-5,5-dialkylhydantoin used in forming said microbiocidalsolution is N,N′-bromochloro-5,5-dimethylhydantoin.
 40. A method as inclaim 37 wherein the microbiocidal solution used in said contacting hasa bromine residual as Br₂ of about 400 ppm (wt/wt) or less as freebromine.
 41. A method as in claim 40 wherein said bromine residual asBr₂ is in the range of about 0.5 to about 200 ppm (wt/wt) as freebromine.
 42. A method as in claim 40 wherein said bromine residual asBr₂ is in the range of about 0.5 to about 100 ppm (wt/wt) as freebromine.
 43. A method as in claim 40 wherein said bromine residual asBr₂ is in the range of about 0.5 to about 50 ppm (wt/wt) as freebromine.
 44. A method as in any of claims 28-30 wherein the method isapplied to at least one raw meat product and wherein said raw meatproduct is at least one ground raw meat product.
 45. A method as inclaim 44 wherein said at least one ground raw meat product is comprisedof ground beef.
 46. A method as in claim 44 wherein said at least oneground raw meat product is comprised of ground pork.
 47. A method as inclaim 44 wherein said at least one ground raw meat product is comprisedof ground raw sausage meat comprised of at least ground beef and/orground pork.